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    <title>Document</title>
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<body>
    <script>
        function timer(t) {
            return new Promise(resolve => {
                setTimeout(() => {
                    resolve("data-" + t)
                }, t)
            })
        }
        async function test() {
            let arr = [timer(1000), timer(2000), timer(3000)]
            for (let item of arr) {
                console.log("start-", Date.now())
                console.log(await item)
                console.log("end-", Date.now())
            }
        }
        test()
    </script>
</body>

</html>